You are given a sentence and a question. You're expected to write the correct answer based on the sentence.

Sentence: John likes to snow tube in the winter and tube down sand dunes in the summer. He notices he can attain greater speeds overall when he snow tubes. Question: Which surface has higher friction?
Sand

Sentence: Annabel rolls a pomegranate down two boards, one with knots and one without. When it rolls down the board without knots, it has less friction than when it rolls down the board with knots. Question: Which board is rougher?
wood board with knots

Sentence: Mary and Tim were going on a trip.  They were both driving their cars.  Both were driving at the same speed and left at the same time.  However, Mary stopped at four in the afternoon, while Tim drove until it was dark. Question: Who drove farther?

Tim

